A home base station is a small radio base station, also known as a “Femto base station,” “pico base station,” or “micro base station” in some contexts. The coverage area for the home base station is relatively small as compared to a cell covered by a standard macro radio base station. The end users can move home base stations geographically from place to place without the operator being able to control relocation of the home base station.
Home base stations may determine their own operating frequency and physical cell identifier. Due to this, it is possible that one or more home base stations and macro base stations end-up having the same physical cell identifier and frequency in the same area leading to interference among cells.
On determination of the above situation, a home base station may be required to change its operating parameters like physical cell identifier/frequency to avoid high level interference. However, a mobile station being served by the home base station may not be aware that the home base station has changed the physical cell identifier. Consequently, the mobile station performs autonomous search for the serving home base station and may fail in locating the serving home base station leading to a communication failure with the home base station and also loss of battery power of the mobile station. Subsequently, the mobile station performs a re-association procedure with other home base station or a macro base station in its proximity. This may cause delay in resumption of service to the mobile station.
One of the currently known systems enables a serving home base station to provide physical cell identifier information to associated mobile stations. The serving home base station specifically sends a message which includes physical cell identifier information and a time stamp to each of the associated mobile stations. The time stamp in the message indicates when the serving home base station is going to use a new physical cell identifier so that the associated mobile stations can use the new physical cell identifier to communicate with the home base station. Further, one or more mobile stations may receive the message from the serving home base station if one or more mobile stations are in connected mode. On the contrary, mobile stations which are not in connected mode may not receive any notification message. Even if the one or more mobile stations are in connected mode, there may be delay in receiving the message by the one or more mobile stations and hence delay may be caused in using the new physical cell identifier indicated in the message by the one or more mobile stations. As a result, the one or more mobile stations may experience failure in a radio link with the serving home base station.